Surveys of fine-scale distributions of naturalized populations of ryegrasses, and analysis of ecological impacts of endophyte infection

非本土牧草植物担心它们对河边和农田的影响，因为它们经常归化到那里入侵。我们选择多花黑麦草作为模式植物，建立了研究黑麦草归化种群的精细分布的方法。利用这种方法，我们记录了多花黑麦草在河边的分布与内生真菌侵染的关系。内生菌感染的个体不太可能被食籽昆虫吃掉，这表明内生菌可能对这些昆虫产生抗性，从而增强了草的侵袭性。我们还在稻田周围发现了抗草甘膦的多花黑麦草。这是日本首次报道一种抗草甘膦杂草。

Non-native pasture plants are concerned about their impacts in both the riversides and farmlands, because they have often naturalized to invade there. We selected ryegrasses as model plants, and developed the method of examining fine-scale distributions of naturalized populations. By using this method, we recorded the distributions of Italian ryegrass in relation to endophyte infection in the riversides. Endophyte-infected individuals were unlikely to be consumed by seed-eating insects, suggesting that endophyte may confer the resistance to those, thereby enhancing the invasiveness of the grass. We also found glyphosate-resistant Italian ryegrass around the rice paddy fields. This is the first report of a glyphosate-resistant weed in Japan.